1. Field
In general, the inventive arrangements relate to diagnostic cardiology, and more specifically, to self-administering electrocardiogram (“ECG”) examinations at locations remote from traditional points-of-care.
2. Description of Related Art
For illustrative, exemplary, representative, and non-limiting purposes, preferred embodiments of the inventive arrangements will be described in terms of cardiac monitoring. However, the inventive arrangements are not limited in this regard.
Now then, syncope (i.e., sudden loss of consciousness) and arrhythmias (i.e., abnormal rhythms) resulting from electrical instability within the heart are particularly challenging for cardiologists to observe. These events can be of short duration and sudden onset, and they often occur infrequently. Early diagnosis of arrhythmias is important, however, because there is a greater likelihood that a patient may suffer a heart failure, stroke, permanent damage, and/or death depending on how long a particular arrhythmia continues undetected and/or untreated. Several arrhythmia-related diseases, such as genetic Long QT Syndrome (LQTS), Wolff-Parkinson-White Syndrome, and Brugada Syndrome, for example, are genetic; others, such as drug-induced LQTS, can be acquired using certain pharmaceuticals.
One effective method for diagnosing arrhythmia-related problems and/or the like involves using electrocardiograms (“ECGs”) for monitoring the electrical activity in a subject's heart. Typically, electric leads are placed on the subject's body at specific locations, and the electrical activity resulting from the heart's polarization and depolarization is then recorded by each lead. During a typical cardiac cycle, for example, the ECG produces a distinctive waveform, often comprising a P-wave, QRS complex, and T-wave, which can then be analyzed to diagnose and/or assess the efficacy of a treatment, such as, for example, a particular drug therapy.
Often, portable ECG recorders are used to collect ECG data from patients after an initial ECG is taken at a physician's office, clinic, and/or other healthcare facility, likely using a traditional, on-site, non-ambulatory ECG recorder. ECG recordings from these portable devices can be used to detect abnormalities in the electrical activity of a patient's heart, which can be caused, for example, by a patient's routine activities and/or heightened emotional and/or physical states.
Commonly, such portable ECG recorders are constructed of two types. The first type is a time-delayed system, which can analyze collected data after completing a collection phase. The second type is a real-time system, which can analyze data in real-time or near real-time as it is recorded.
In either type, the ECG signals are typically received from a plurality of leads that are attached between electrodes running between various points on the patient's body and/or an associated unit worn about the patient's neck, waist, wrist, and/or the like. Unfortunately, however, most, if not all, of the common portable, non-ambulatory devices are bulky and interfere with patients' normal lives. As a result, patient compliance cannot be relied upon to ensure proper use of ECG recording devices.
Other problems with body-worn, lead-type monitors include their inability to avoid attendant skin irritation. Results from such monitors can also vary depending on where various electrodes are placed on the patient's body. In addition, most leads need to be removed before showering, bathing, and/or other water exposure, as well as other activities.
Recently, portable, non-ambulatory ECG recording devices have become available that can operate on tactile-sensing from fingers and/or thumbs and/or hands of a patient without requiring placing leads and/or electrodes all over the patient's body. Such devices are often designed to be retained by patients long term, particularly as continuous-use monitors and/or recorders capable of displaying real-time results and/or subsequently transferring collected data to remote locations for time-delayed analysis.
In any event, many currently portable designs, while offering advantages over the prior art, are expensive to produce and maintain, and they are not generally intended for large-scale use. Accordingly, it is appropriate to consider new ECG devices that are affordable, self-contained, portable, disposable, designed for limited-use and/or large-scale use, and/or returnable to a central location for analyzing collected ECG data.
One scenario that exemplifies this need for improved portable, non-ambulatory, tactile-sensing ECG recording devices relates to dispensing new pharmaceuticals. For example, as is well-known, new drugs are subject to a rigorous evaluation process, from compound discovery to final approval, which can require years of trials and millions of dollars. Typically, new drugs are evaluated with progressive screening throughout so-called Phase I, II, and III clinical trials. Even after Phase III approval of a drug is received, however, there often remains a follow-up desire and/or requirement to perform a so-called Phase IV trial, which is also known as post-market surveillance. These Phase IV trials can be prudent even if a drug shows few complications during its Phase II and III trails, particularly as the drugs are dispensed to increasingly larger numbers of patients. Accordingly, new techniques are desirable, particularly during Phase II-IV trials, to allow for more ECGs to be acquired for review, without the necessity and burden of returning to a physician's office and/or other medical facility.
One critical component of this drug follow-up includes recording ECG signals, primarily to look for the existence of drug-induced LQTS and/or the like. As previously alluded to, LQTS describes an abnormality of the heart's electrical system, predisposing certain affected persons to dangerous heart rhythms, e.g. Torsade de Pointes, which can lead to a sudden loss of consciousness and/or death. As known, however, ECG recording devices can be used to measure QT intervals and screen for LQTS.
In a common scenario, a patient will take a particular medication for a particular period of time and then return to his or her physician's office, clinic, and/or other healthcare facility and/or the like that has a large, stand-alone ECG recorder. Unfortunately, repeatedly returning to such a facility can be expensive, time consuming, and impractical, particularly when drug-monitored patient populations exceed tens and hundreds of thousands of participants.
Besides drug-induced LQTS, it is also prudent to monitor for congenital LQTS, which is a genetic and/or inherited condition that can lead to fatal arrhythmias. Unfortunately, many of these types of arrhythmias can occur in young children during physical exertion (e.g., while exercising, playing an aerobic sport, and/or the like), and they are often fatal. Accordingly, an improved portable ECG recording device would allow for inexpensive screening of students, athletes, and/or the like to look for heart problems at an early age, particularly in a manner which is generally unavailable today.
Additionally, hospitals are prone to infections. For example, patients with severe infections, such as Methycillin-Resistant Staphylococcus Aureus (“MRSA”), may require monitoring ECG signals. However, after an MRSA ECG recording session, the ECG recording device must often be disinfected before it can be used again. Often, this involves detailed cleaning using severe cleaning agents, which can damage, and eventually destroy, the ECG leads. Accordingly, it is also important to consider new ECG recording techniques that can minimize problems associated with controlling infections.
In accordance with the foregoing, it is desirable to provide an improved, easy-to-use, portable, non-ambulatory, tactile-sensing ECG recording device that can be produced inexpensively, in large quantities, and adapted for large-scale use outside a traditional ECG facility. Such devices may be customized for particular patients picking up particular prescriptions, as well as for aggregated and/or other generalized screening purposes. It is also desirable to provide ECG recording devices that can be returned to a central location for further review and analysis following ECG data collection activities.